Trigger mechanism for initiating a phase change in a variable liquid element

ABSTRACT

A trigger mechanism used for initiating a phase change in a variable liquid element by an activating material. The trigger mechanism also relates to a variable liquid element enclosed in a container with at least one perforation in the container, an activating material, and a movable barrier means for bringing the activation material into contact with the perforation.

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application is a continuation application of prior copendingInternational Application No. PCT/US02/16047, filed May 21, 2002,designating U.S., which claims the benefit of U.S. ProvisionalApplication No. 60/294,843, filed May 31, 2001.

FIELD OF THE INVENTION

[0002] The present invention relates to a trigger mechanism forinitiating a phase change in a variable liquid element by an activatingmaterial. The trigger mechanism also relates to a variable liquidelement enclosed in a container with at least one perforation in thecontainer, an activating material, and a movable barrier means forbringing the activation material into contact with the perforation.

BACKGROUND OF THE INVENTION

[0003] It is generally said that there are three principle states ofmatter—gas, liquid, and solid. While the transition between the threestates is generally unhindered, occasionally external forces initiatethe transition. For example, some liquids, called supercooled solutions,require a seed crystal to initiate the transition from liquid to acrystalline solid.

[0004] The use of supercooled solutions for providing heat is well knownin the art. Certain salts once melted into a solution will remain liquidat a temperature below the melting point of the salt. On solidification,these supercooled solutions give up heat. Typically, water/saltcombinations are used to make such supercooled solutions. In order toinitiate heat dissemination, the supercooled solution must begin tosolidify. Several techniques are known to initiate solidification.

[0005] One method for initiating solidification involves introducing acrystal or another type of nucleating particle into the supercooledsolution. Previously suggested forms for this type of initiation includethe use of flexible metal strips, usually with holes or slits that areplaced into the supercooled solution. Examples are illustrated in U.S.Pat. No. 4,077,390; U.S. Pat. No. 4,379,448; U.S. Pat. No. 4,460,546;U.S. Pat. No. 4,572,158; U.S. Pat. No. 5,736,110; and U.S. Pat. No.5,915,461. The use of a helically-coiled, resilient metallic filamentthat initiates crystallization when rubbing action is sufficient toinitiate solidification is discussed in U.S. Pat. No. 4,829,980. Theseinitiation techniques are generally confined to a specific locationwithin the solution for easier activation by the user.

[0006] Other forms for initiation of solidification of a supercooledsolution include a puncturing device that admits air into thesupercooled solution and thereby initiates crystallization, see U.S.Pat. No. 5,305,733 and U.S. Pat. No. 5,662,096. Coating the nucleatingparticles and placing the coated nucleating particles directly into thesupercooled solution is discussed in U.S. Pat. No. 6,103,139.

[0007] Each of these forms for initiation contains drawbacks that aresolved by the present invention. The inclusion of the nucleatingparticle or device within the supercooled solution results in prematureinitiation of the solidification of a supercooled solution, whichresults in unreliability. Puncture methods also tend to be unreliablesince the puncturing forces can be accidentally activated duringtransportation or storage of the product. Puncture methods are alsoundesirable when the supercooled solution is being used to heat anotherproduct where contamination of the product is undesirable. Thus thereremains a need for a safe and reliable mechanism for initiating phasechanges for liquids through activating materials such as nucleatingparticles.

SUMMARY OF THE INVENTION

[0008] The present invention relates to a trigger mechanism forinitiating a phase change in a variable liquid element by an activatingmaterial. The trigger mechanism also relates to a variable liquidelement enclosed in a container having at least one wall, an activationmaterial located external to the container of the variable liquidelement, at least one perforation in the container wall, and a movablebarrier means for bringing the activation material into contact with theperforation. The movable barrier means seals the perforation andisolates the perforation and the activation material so that thevariable liquid element is not activated until the movable barrier meansis initiated by the user.

[0009] These and other features, aspects, advantages, and variations ofthe present invention will become evident to those skilled in the artfrom a reading of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] While the specification concludes with claims particularlypointing out and distinctly claiming the invention, it is believed thatthe invention will be better understood from the following descriptionof the accompanying figures, not necessarily drawn to scale, in which:

[0011]FIG. 1 is a top view of one preferred embodiment of the triggermechanism having a one-piece configuration in an unfolded orientation;

[0012]FIG. 2 is a side view of the trigger mechanism shown in FIG. 1taken along section line 2-2 on a container;

[0013]FIG. 3 is a top view of the trigger mechanism shown in FIG. 1 on acontainer;

[0014]FIG. 4 is a top view of another preferred embodiment of theone-piece trigger mechanism having a one-piece configuration in anunfolded orientation;

[0015]FIG. 5 is a side view of the trigger mechanism shown in FIG. 4taken along section line 5-5 on a container;

[0016]FIG. 6 is a top view of the trigger mechanism shown in FIG. 4 on acontainer;

[0017]FIG. 7 is a partial view of a container with a preferredembodiment of a two-piece trigger mechanism attached to a package with aperforation in a wall of the package;

[0018]FIG. 8 is a view of the base tape of the trigger mechanism shownin FIG. 6 after it has been folded to bring the activation material intocontact with the perforation in the wall of the container;

[0019]FIG. 9 is a top view of a preferred embodiment of a two-piecetrigger mechanism in an unfolded orientation;

[0020]FIG. 10 is a view of a preferred embodiment of a two-piece triggermechanism attached to a container with a perforation in a wall of thepackage; and

[0021]FIG. 11 is another preferred embodiment of the trigger mechanismshown in FIG. 10 in a one-piece configuration.

DETAILED DESCRIPTION OF THE INVENTION

[0022] All percentages, ratios and proportions herein are by weight ofthe final composition, unless otherwise specified. All temperatures arein degrees Celsius (° C.) unless otherwise specified. All documentscited are incorporated herein by reference in their entireties. Citationof any reference is not an admission regarding any determination as toits availability as prior art to the claimed invention.

[0023] Variable Liquid Element

[0024] A variable liquid element as used herein means any material thatchanges color, temperature, phase and/or another physical property whenactivated by a seed crystal or other nucleating particle. An example isa supercooled salt solution that can be initiated with a nucleationparticle. Sodium formate (HCOONa), potassium formate (HCOOK), sodiumacetate (CH₃ COONa), magnesium acetate [(CH₃COO)₂Mg], potassium nitrate(KNO₃), calcium nitrate [Ca(NO₃)₂₁, sodium thiosulfate (Na₂S₂O₃),dipotassium hydrogen phosphate (K₂HPO₄), and urea [(NH₂)₂CO], or anyother similar salts and mixtures thereof are examples of suitable salts.The variable liquid element may also include additives for controllingthe rate of reaction such as those discussed in U.S. Pat. No. 4,331,556.U.S. Pat. No. 4,331,556 discloses a method of combining a crystallizingmaterial with a liquid additive that has properties of forming ametastable solid together with the crystallizing material. When theliquid additive exsolves, the crystalline aggregate is weakened and iseasily decomposed into fragments of small size. The liquid additivematerials may include monohydric alcohols, diols and triols. The liquidadditive material may be included in the liquid to be crystallized, insmall amounts, amounts to two percent (2%) to five percent (5%) beingtypical. The amount and relative metastability of the liquid additivematerial in the solution contributes to control of the size of thecrystals that are ultimately produced when the supercooled fluidcrystallizes. A small amount of surface-active material may also beincluded to modify the characteristics of the metastable solid solution,the exsolution process, and the texture of the exsolved crystalaggregate.

[0025] Other materials that can be added to the variable liquid elementare gelling agents such as those discussed in US RE035586 or U.S. Pat.No. 5,065,598, which teach the use of one or more materials selectedfrom the group consisting of natural and synthetic gums and gum-likematerials such as gelatin; cellulose derivatives such as methylcellulose and carboxymethylcellulose sodium salt; superabsorbants suchas hydrolyzed acrylonitrile grafted starch; synthetic polymer orcopolymer which is hydratable and cross-linkable in solution, such aspolyacrylates and copolymers of acrylic acid and polyallyl sucrose knownas CARBOMER™ from B.F. Goodrich Chemical Company; polyethylene glycol,and any other similar additives known in the art, and mixtures thereof.

[0026] Container

[0027] The trigger mechanism of the present invention is desirably usedwith a container that holds the variable liquid element or contains thevariable liquid element and another product. The container may compriseany container having one or more non-deformable or generally flexibleand/or deformable outer surface such as a wall that allows pressure tobe applied through the outer surface to at least a portion of thevariable liquid element in order to activate the variable liquidelement. The container, for example, may comprise a flexible bottle, aflexible tube, a flexible tub, a sachet, a pouch, a stand-up pouch, aflexible thermoformed container, cartons or the like. The container maybe comprised of one or more polymeric materials, metallized structures,laminate structures, lined paperboards, co-extruded films and the like.

[0028] If the variable liquid element provides a temperature change, thecontainer may also include some form of insulation, such as insulationlayers, that insulates the exterior of the container from the internalvariable liquid element and increases the efficiency of the temperaturechange. The insulation layer may extend over substantially the entireexterior and/or interior surface of the container, may extend over atleast a portion of the exterior and/or surface of the containercorresponding to about the size of the variable liquid element, maycover a portion of the exterior and/or interior of the outer containerthat a consumer might touch during the temperature change process. Theinsulation layer may be a separately attached layer or an integral partof the material forming the container such as a co-extruded or laminatedstructure. Examples of possible insulating materials include, but arenot limited to, foamed polyethylene, silicone rubber, a fibrouscellulose structure, or a dimpled thermoformed film with a rigidthickness to provide air pockets as insulation (lattice with a largeamount of void space) and the like.

[0029] The container may be formed and/or sealed in any manner known inthe art. For example, an outer container formed out of a polymeric filmmay be sealed via one or more of the following: heat sealing, ultrasonicbonding, radio frequency bonding, adhesive bonding, etc.

[0030] If the container is to be used for providing a temperature changefor products such as liquids, shampoos, oils, waxes, emollients,lotions, moisturizers, medicaments, pastes, surfactants, gels,adhesives, suspensions, solutions, enzymes, soaps, cosmetics, liniments,beverages, soups, cheeses, flowable particulates and the like, then thecontainer's external surface may also include a useful layer that may beused to perform a function related to the product contained in thepackage. A container containing a hair treatment product, for example,may include bristles or tines on the outside surface of the outercontainer to aid in dispensing the product onto hair follicles. Acontainer containing a skin lotion may include an abrasive surface thatmay be used to exfoliate the user's skin before or after the lotion isapplied. The container may also include an absorbent structure that mayaid in removing a product from a target surface to which the product hasbeen applied.

[0031] In another embodiment, the container may be attached to or housedwithin a device that may assist in using or dispensing of the product.In the case of a hair treatment product, for example, the container maybe housed within a hair-brush or comb that spreads the hair treatmentonto hair follicles. Alternatively, a container having a cleaningsolution may be housed inside a sponge, brush, wipe, abrasive scrubbingimplement, etc. that may be used to scrub a target surface using theproduct from the container.

[0032] The container may further include an optional opening means. Forexample, the opening means may be, but not limited to, rupturablebarriers such as frangible seals, perforations, tear strips, ZIPLOCK™,and the like. Alternatively, the container may be cut open to access theproduct. The opening may also be sized or designed to prevent thevariable liquid element from exiting the container when the product isdispensed if the variable liquid element is not otherwise attached orrestrained within the container. For example, the opening may include atapered dosing channel to prevent the variable liquid element fromexiting the container during use. The container may also include adispensing attachment such as a spout, an applicator tip, spray head orthe like in order to aid in product dispensing.

[0033] Perforation

[0034] The perforation is formed in at least one wall of the container.The perforation can be a puncture, a hole, a slit, a crack, a crevice,or any other similar opening that can be formed in the wall of thecontainer by piercing the wall of the container with hot needles, coldneedles, vacuum forming, or high pressure water jet forming or any othermethod known in the art.

[0035] Activation Material

[0036] Activation material as used herein means a nucleating particle orseed crystal that, when in contact with the variable liquid element, cancause the desired physical property change. The activation material isbrought into contact with the variable liquid element through theperforation contained in the wall of the container. Preferableactivation material is a crystal comprising the same material as thevariable liquid element. The activation material is keep isolated fromthe perforation in the wall of the container by the movable barriermeans, discussed below.

[0037] Movable Barrier Means

[0038] The movable barrier means of the present invention is a devicethat, when activated by a user, initiates the phase change of thevariable liquid element. The movable barrier means remains inactivateduntil an event, such as pressure or motion, causes the movable barriermeans to be activated. The purpose of the movable barrier means is toisolate the variable liquid element from the activation material.

[0039] The movable barrier means is located external to the containersuch that the movable barrier means protects the activation materialfrom external contact as well as provides a removable barrier to theperforation in the wall of the container. For example, the movablebarrier means may comprise a folded tab that is activated by a user. Themovable barrier means seals, by adhesive or other suitable sealingmeans, the perforation in the container wall and at the same timeisolates the activation material from the variable liquid element. Whenthe user activates the movable barrier means, the movable barrier meansopens and brings the activation material into contact with a perforationin the container wall.

[0040] The activation material may be printed, coated, sprayed, orotherwise be deposited upon a section of the movable barrier means. Themovable barrier means is then folded or oriented so that the activationmaterial is not exposed to the perforation in the container wall.Similarly the activation material should not be exposed on the outsidesurface of the movable barrier means. The movable barrier means may beperforated or scored to make for easy tearing or opening by a user. Themovable barrier means is placed over the perforation in the containerwall that holds the variable liquid element. The movable barrier meansmay be activated by pulling or lifting so that the activation materialcomes into contact with the perforation.

[0041] In one preferred embodiment of the movable barrier means 20,shown in FIGS. 1, 2 and 3, the movable barrier means 20 is made from onepiece of material, such as a plastic laminate or other suitablematerial, comprising an outer cover 22, an inner cover 24, and apull-tab 26. Activation material 28 is located on a portion of the outercover 22. The inner cover 24 contains vertical tear zones 30 whichextend from the sides of the pull-tab 26 toward the outer cover 22through the inner cover 24. The vertical tear zones 30 preferablyterminate at a horizontal tear zone 32. The horizontal tear zonepreferably comprises a portion of fold line 34. The fold line 34 islocated between the outer cover 22 and the inner cover 24.

[0042] The outer cover 22 is folded along fold line 34 onto the innercover 24 and partially onto the pull-tab 26; see FIG. 2. Thus, theactivation material 28 is located between the outer cover 22 and theinner cover 24 and there remains isolated until the user wished toinitiate activation of the movable barrier means 20. The movable barriermeans 20 is preferably attached to a container 56 with a perforation 60in the container 56.

[0043] The movable barrier means 20 is activated when the user pulls thepull-tab 26 with a horizontal motion. The vertical tear zones 30 andhorizontal tear zone 32 break away and expose the activation material 28to the perforation 60 in the container 56.

[0044] Another preferred embodiment of a movable barrier means 120,shown in FIGS. 4, 5 and 6 comprises one piece of material, such as aplastic laminate or other suitable material, which is comprised of threesections. The first section, cover 136, is preferably rectangular innature, but can be any suitable shape, and is the largest of the threesections.

[0045] The cover 136 is separated by fold line 144 from the secondsection. The second section comprises two sub-sections, crown area 138 aand center area 138 b, which are orientated in a “T” shape. The crownarea 138 a and the center area 138 b are separated by fold line 146. Thecrown area 138 a contains vertical tear zones 130 extending from thesides of the center area 138 b, through the crown area 138 a andpreferably terminating at fold line 144.

[0046] The center area 138 b is separated by fold line 142 from thethird section. The third section comprises two sub-sections, top area140 a and the middle area 140 b, also orientated in a “T” shapestructure. The top area 140 a and the middle area 140 b are separated byfold line 148. The top area 140 a contains vertical tear zones 130extending from the sides of the middle area 140 b, through the top area140 a, and preferably terminating at fold line 148.

[0047] Activation material 128 preferably is placed on an areaencompassing a portion of cover 136 and crown area 138 a. Cover 136 isthen folded over crown area 138 a along fold line 144 so that theactivation material 128 is enclosed between cover 136 and crown area 138a. Crown area 138 a and center area 138 b are folded along fold line 146in the opposite direction that cover 136 was folded onto crown area 138a, as shown in FIG. 5. Similarly, top area 140 a and middle area 140 bare folded along fold line 148 in the same direction as fold line 146,as shown in FIG. 5. Center area 138 b and middle area 140 b areorientated to align by folding fold line 142.

[0048] The movable barrier means 120, shown in FIG. 6, is preferablyconnected to a container 156 having a perforation 160 in the container156 wall. The movable barrier means 120 is connected to the container156 over the perforation 160 by attaching the top area 140 a to one sideof the perforation 160 and the crown area 138 a located over theperforation 160. The movable barrier means 120 results with the middlearea 140 b superpose over the top area 140 a, the center area 138 bsuperposed over the middle area 140 b, the crown area 138 a superposedover the center area 138 b and the cover 136 superposed over the crownarea 138 a; see FIG. 5. The cover 136 is preferably adhesively connectedto container 156 around the crown area 138 a.

[0049] The movable barrier means 120 is activated when the user pullscenter area 138 b and middle area 140 b in a horizontal direction. Whenthe movable barrier means 120 is activated, the vertical tear zones 130tear away and expose the activation material 128 to the perforation 160in the container 156.

[0050] Another preferred embodiment of the movable barrier means 220 isshown in FIGS. 7 and 8. The movable barrier means 220 comprises a toptab 250 and a bottom tab 252. Each tab is comprised of a plasticlaminate or any other such suitable materials. The activation material228 is placed on a small area of the bottom tab 252. The bottom tab 252is connected to the first side 254 of the container such that the smallarea with the activation material 228 is not in contact with the outersurface of the container. The top tab 250 is adhesively connected to thesecond side 256 of the container in the same area and in the sameorientation as the top tab 250. The movable barrier means 220 isactivated when the user removes the top tab 250 from the second side 256of the container and folds the bottom tab 252 around the edge of thecontainer 258 so that the activation material 228 comes into contactwith a perforation 260 in the second side 256 of the container, as shownin FIG. 8.

[0051] Another preferred embodiment of the movable barrier means 320,shown in FIGS. 9 and 10, comprises two pieces of material, cover tape362 and base tape 364. The tapes are comprised of a plastic laminate orother suitable material. The cover tape 362 is printed, coated, sprayed,or otherwise deposited with activation material 328 on a portion of itssurface.

[0052] The base tape 364 is preferably folded along fold line 366 tocreated an area that is easily grasped by the user but still have anarea secured to a container 356, but such folding is not required. Thebase tape 364 is then adhesively placed over a perforation 360 in acontainer 356. The cover tape 362 is then adhered to the container 356,over a portion of the base tape 364. The movable barrier means 320 maybe activated by pulling or lifting the base tape 364 so that it isremoved from its position between the perforation 60 in the container356 and the cover tape 362.

[0053] This preferred embodiment alternatively may comprise a singlepiece of material, such as a plastic laminate or other suitablematerial, such as shown in FIG. 11 with an additional fold line 370where the cover tape 362 superposed over the base tape 364.

[0054] It is understood that the preferred embodiments of the presentinvention are not limiting to the scope and understanding of the presentinvention.

[0055] All documents cited in the Detailed Description of the Inventionare, in relevant part, incorporated herein by reference; the citation ofany document is not to be construed as an admission that it is prior artwith respect to the present invention.

[0056] While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A trigger mechanism for initiating a phase changein a variable liquid element comprising: a) a variable liquid elementenclosed in a container having at least one wall; b) an activationmaterial located external to the wall of the container; c) at least oneperforation in the container wall; d) a movable barrier means forbringing the activation material into contact with the perforation;wherein the movable barrier means isolates the activation material fromthe perforation so that the phase change in the variable liquid elementis not activated until the movable barrier means is initiated by a user.2. The trigger mechanism of claim 1 wherein the movable barrier meansfurther comprises a folded tab wherein the activation material isprinted, coated, sprayed, or any combination thereof, onto the foldedtab; the folded tab is externally connected to the container over theperforation and the folded tab isolates the activation material from theperforation.
 3. A trigger mechanism of claim 1 wherein the containerfurther contains a product, and wherein the phase change in the variableliquid element provides a temperature change to the product.
 4. Atrigger mechanism of claim 1 wherein the variable liquid element is asupercooled salt solution.
 5. A trigger mechanism of claim 1 wherein theperforation is a puncture, a hole, a slit, a crack, a crevice, or anycombination thereof.
 6. A trigger mechanism for initiating a phasechange in a variable liquid element comprising an activation materialprinted, coated, sprayed, or any combination thereof onto a folded tab,the folded tab being externally connected to a container having at leastone wall with at least one perforation in the wall, the containerfurther enclosing a variable liquid element, wherein the activationmaterial is isolated from the perforation by the folded tab until thefolded tab is activated by the user thereby bringing the activationmaterial into contact with the perforation and initiating a phase changethe variable liquid element.
 7. The trigger mechanism of claim 5 whereinthe variable liquid element is a supercooled salt solution.
 8. Thetrigger mechanism of claims 6 wherein the container further contains aproduct, and wherein the phase change in the variable liquid elementprovides a temperature change to the product.